Method of inspecting a specimen and system thereof

Abstract

There are provided a method of generating an inspection recipe usable for inspecting an inspection area of a specimen and a recipe generating unit. The recipe generating unit is configured: upon obtaining design data informative of design structural elements comprised in a design PoI corresponding to the at least one PoI, to provide global segmentation of a test image captured by an inspection tool unit from the inspection area and comprising at least one test PoI of substantially the same design as the at least one PoI, thereby to obtain segmented structural elements comprised in the test PoI and segmentation configuration data; to associate the segmented structural elements comprised in the test PoI with the design structural elements comprised in the design PoI, thereby to obtain design association data; and to generate an inspection recipe comprising, at least, segmentation configuration data and design association data.

The invention claimed is: 
     
       1. A method to generate an inspection recipe for inspecting an inspection area of a specimen, the inspection area comprising at least one pattern of interest (PoI), the method comprising:
 obtaining design data that includes design structural elements in a design PoI that corresponds to the at least one PoI; 
 in response to obtaining the design data, providing global segmentation of a test image captured from the inspection area and comprising at least one test PoI of substantially the same design as the at least one PoI to obtain segmented structural elements in the test PoI and segmentation configuration data; 
 associating the segmented structural elements in the test PoI with the design structural elements in the design PoI to obtain design association data; and
 generating, by a processing device, the inspection recipe comprising:
 the segmentation configuration data for local segmentation of at least one inspection PoI in an inspection image to be captured from the inspection area, the local segmentation to yield inspection structural elements; and 
 the design association data to associate at least part of the inspection structural elements with the design structural elements by assigning an identification of the design structural elements from the design data to pixels of the test image that correspond to the at least part of the inspection structural elements and specifying an offset between a position of a respective inspection structural element of the inspection structural elements and another position of a respective design structural element of the design structural elements, and wherein the design association data is to be used for one or more metrology measurements for one or more of the inspection structural elements corresponding to at least one metrology target. 
 
 
 
     
     
       2. The method of  claim 1 , further comprising:
 prior to associating the segmented structural elements with the design structural elements, registering the test image in design data coordinates and obtaining position calibration data, wherein the generated inspection recipe further comprises the position calibration data for registering in design data coordinates the inspection image to be captured from the inspection area. 
 
     
     
       3. The method of  claim 2 , wherein associating the segmented structural elements with the design structural elements comprises:
 assigning, to each design structural element, a unique identifier; 
 using design data coordinates of the test PoI to identify design structural elements corresponding to segmented structural elements; and 
 for each of the segmented structural elements, assigning, to a given segmented structural element and corresponding pixels, the same unique identifier as the corresponding design structural element. 
 
     
     
       4. The method of  claim 1 , wherein the design association data comprises an association data structure associating, for each of the segmented structural elements, each of the pixels corresponding to a given segmented structural element in the test PoI with a unique identifier of a design structural element associated with the given segmented structural element. 
     
     
       5. The method of  claim 1 , wherein the test image comprises a plurality of test PoIs with substantially the same design, the method further comprising:
 for each of the segmented structural elements in each PoI of the plurality of PoIs, associating a given segmented structural element with a respective design structural element in the design PoI to obtain design association data informative of an association of each of the pixels corresponding to the segmented structural elements in the plurality of test PoIs with identifications (IDs) of respectively associated design structural elements. 
 
     
     
       6. The method of  claim 1 , wherein the generated inspection recipe further comprises metrology data informative of at least one metrology target. 
     
     
       7. The method of  claim 6 , wherein at least one metrology measurement to be provided for the one or more inspection structural element is selected from at least one of:
 extracting measurement information indicative of discrepancy related to dimensions and/or shape of an inspection structural element in comparison to corresponding design structural element identified using the design association data; 
 extracting measurement information indicative of discrepancy in distances between inspection structural elements in comparison to corresponding design structural elements identified using the design association data; and 
 extracting measurement information indicative of overlay discrepancy associated with inspection structural elements in comparison to corresponding design structural elements identified using the design association data. 
 
     
     
       8. A system to generate an inspection recipe to inspect an inspection area of a specimen, the inspection area comprising at least one pattern of interest (PoI), the system comprising:
 a memory; and 
 a processor, operatively coupled with the memory, to:
 obtain design data that includes design structural elements in a design PoI that corresponds to the at least one PoI; 
 in response to obtaining the design data, provide global segmentation of a test image captured by an inspection tool unit from the inspection area and comprising at least one test PoI of substantially the same design as the at least one PoI to obtain segmented structural elements in the test PoI and segmentation configuration data; 
 associate the segmented structural elements in the test PoI with the design structural elements in the design PoI to obtain design association data; and 
 generate the inspection recipe based on the segmentation configuration data and the design association data, the segmentation configuration data being for local segmentation of at least one inspection PoI in an inspection image to be captured from the inspection area, wherein the local segmentation is to yield inspection structural elements, and wherein the design association data is to associate at least part of the inspection structural elements with the design structural elements by assigning an identification of the design structural elements from the design data to pixels of the test image that correspond to the at least part of the inspection structural elements and specifying an offset between a position of a respective inspection structural element of the inspection structural elements and another position of a respective design structural element of the design structural elements, and wherein the design association data is to be used for one or more metrology measurements for one or more of the inspection structural elements corresponding to at least one metrology target. 
 
 
     
     
       9. The system of  claim 8 , wherein the processor is further to register, prior to associating the segmented structural elements with the design structural elements, the test image in design data coordinates and to obtain position calibration data and to include the position calibration data in the generated inspection recipe. 
     
     
       10. The system of  claim 8 , wherein the processor is further to:
 assign, to each design structural element, a unique identifier; 
 use design data coordinates of the test PoI to identify design structural elements corresponding to segmented structural elements; and 
 for each of the segmented structural elements, assign to a given segmented structural element and corresponding pixels the same unique identifier as the corresponding design structural element to associate the segmented structural elements with the design structural elements. 
 
     
     
       11. The system of  claim 8 , wherein the design association data comprises an association data structure associating, for each of the segmented structural elements, each of the pixels corresponding to a given segmented structural element in the test PoI with a unique identifier of a design structural element associated with the given segmented structural element. 
     
     
       12. The system of  claim 8 , wherein the generating of the inspection recipe is further based on metrology data informative of at least one metrology target. 
     
     
       13. A non-transitory computer usable medium having instructions, which when executed by a processing device, cause the processing device to perform operations to generate an inspection recipe for inspecting an inspection area of a specimen, the inspection area comprising at least one pattern of interest (PoI), the operations comprising:
 obtaining design data that includes design structural elements in a design PoI that corresponds to the at least one PoI; 
 in response to obtaining the design data, providing global segmentation of a test image captured from the inspection area and comprising at least one test PoI of substantially the same design as the at least one PoI to obtain segmented structural elements in the test PoI and segmentation configuration data; 
 associating the segmented structural elements in the test PoI with the design structural elements in the design PoI to obtain design association data; and 
 generating an inspection recipe comprising:
 the segmentation configuration data for local segmentation of at least one inspection PoI in an inspection image to be captured from the inspection area, the local segmentation to yield inspection structural elements; and 
 the design association data for associating at least part of the inspection structural elements with the design structural elements by assigning an identification of the design structural elements from the design data to pixels of the test image that correspond to the at least part of the inspection structural elements and specifying an offset between a position of a respective inspection structural element of the inspection structural elements and another position of a respective design structural element of the design structural elements, and wherein the design association data is to be used for one or more metrology measurements for one or more of the inspection structural elements corresponding to at least one metrology target. 
 
 
     
     
       14. The non-transitory computer usable medium of  claim 13 , the operations further comprising:
 prior to associating the segmented structural elements with the design structural elements, registering the test image in design data coordinates and obtaining position calibration data, wherein the generated inspection recipe further comprises the position calibration data for registering in design data coordinates the inspection image to be captured from the inspection area. 
 
     
     
       15. The non-transitory computer usable medium of  claim 13 , wherein associating the segmented structural elements with the design structural elements comprises:
 assigning to each design structural element a unique identifier; 
 using design data coordinates of the test PoI to identify design structural elements corresponding to segmented structural elements; and 
 for each of the segmented structural elements, assigning to a given segmented structural element and corresponding pixels the same unique identifier as the corresponding design structural element. 
 
     
     
       16. The non-transitory computer usable medium of  claim 13 , wherein the generated inspection recipe further comprises metrology data informative of at least one metrology target. 
     
     
       17. The non-transitory computer usable medium of  claim 13 , wherein the test image comprises a plurality of test PoIs with substantially the same design, the operations further comprising:
 for each of the segmented structural elements in each PoI of the plurality of PoIs, associating a given segmented structural element with respective design structural element in the design PoI to obtain design association data informative of association of each of the pixels corresponding to the segmented structural elements in the plurality of test PoIs with IDs of respectively associated design structural elements. 
 
     
     
       18. The method of  claim 1 , wherein the inspection recipe further comprises a parameter that is adjusted based on an imaging condition associated with the test image.